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991.
992.
993.
Intraoperative ultrasound examination of the brain 总被引:5,自引:0,他引:5
In a preliminary demonstration of cranial intraoperative real-time ultrasound, both supratentorial and posterior fossa scans displayed the pertinent anatomy. A grade III astrocytoma was visualized on the supratentorial scan as well. Ultrasound may be valuable for surgical planning and biopsy procedures because of its reliable depiction of intracranial anatomy and ease of use. 相似文献
994.
OBJECTIVES: Few studies have examined the effects of caregiving on the caregivers of chronically critically ill (CCI) patients, and no one has examined the impact of a disease management program (DMP) on physical and psychological outcomes for the caregivers of CCI patients. The purposes of this study of caregivers of CCI patients were as follows: (1) to describe the characteristics of CCI patients and caregivers and to examine the frequency of depression, subjective burden, and physical health; (2) to examine factors related to depression after hospital discharge; and (3) to examine the effects of a DMP on the physical health, depression, and burden of caregivers 2 months post-hospital discharge. DESIGN: Prospective experimental design.Setting and participants: Caregivers of 290 patients who had received > 3 days of mechanical ventilation while in the ICU of a university medical center. MEASUREMENTS: Sociodemographics, caregiver burden, physical health status, and depression were measured using established tools. RESULTS: Interviews of caregivers were conducted at hospital discharge and 2 months later. Seventy-three percent of patients survived, completed the study period, and required caregiving 2 months later. Caregivers of patients residing in an institution reported higher depression (p = 0.0001), higher burden (ie, disrupted schedule, p = 0.0001; lack of family support, p = 0.036), and greater health problem scores (p = 0.0001) than did caregivers of patients residing at home. The DMP did not have a statistically significant impact on any of the outcome variables. However, by 2 months, 54% of caregivers in the experimental group had no depression or mild depression compared with 34.5% of the control group. CONCLUSION: Two months after hospital discharge, approximately 25% of caregivers were classified as depressed with 16.7% of the depressed group classified as moderately or severely depressed. The caregivers of CCI patients are at risk for post-hospital discharge depression, and the caregivers of institutionalized CCI patients are at highest risk of long-term negative effects from caregiving. 相似文献
995.
The aim of this paper was to review the literature on factors related to role stress in nurses, and present strategies for addressing this issue based on the findings of this review while considering potential areas for development and research. Computerized databases were searched as well as hand searching of articles in order to conduct this review. This review identified multiple factors related to the experience of role stress in nurses. Role stress, in particular, work overload, has been reported as one of the main reasons for nurses leaving the workforce. This paper concludes that it is a priority to find new and innovative ways of supporting nurses in their experience of role stress. Some examples discussed in this article include use of stress education and management strategies; team-building strategies; balancing priorities; enhancing social and peer support; flexibility in work hours; protocols to deal with violence; and retention and attraction of nursing staff strategies. These strategies need to be empirically evaluated for their efficacy in reducing role stress. 相似文献
996.
Strain MC Little SJ Daar ES Havlir DV Gunthard HF Lam RY Daly OA Nguyen J Ignacio CC Spina CA Richman DD Wong JK 《The Journal of infectious diseases》2005,191(9):1410-1418
Patients in whom virologic suppression is achieved with highly active antiretroviral therapy (HAART) retain long-lived cellular reservoirs of human immunodeficiency virus type 1 (HIV-1); this retention is an obstacle to sustained control of infection. To assess the impact that initiating treatment during primary HIV-1 infection has on this cell population, we analyzed the decay kinetics of HIV-1 DNA and of infectivity associated with cells activated ex vivo in 27 patients who initiated therapy before or <6 months after seroconversion and in whom viremia was suppressed to <50 copies/mL. The clearance rates of cellular reservoirs could not be distinguished by these techniques (median half-life, 20 weeks) during the first year of HAART. The clearance of HIV-1 DNA slowed significantly during the subsequent 3 years of treatment (median half-life, 70 weeks), consistent with heterogeneous cellular reservoirs being present. Total cell-associated infectivity (CAI) after 1 year of treatment was undetectable (<0.07 infectious units/million cells [IUPM]) in most patients initiating treatment during primary infection either before (9/9) or <6 months after (6/8) seroconversion. In contrast, all 17 control patients who initiated HAART during chronic infection retained detectable CAI after 3-6 years of treatment (median reservoir size, 1.1 IUPM; P<.0005). These results suggest that treatment <6 months after seroconversion may facilitate long-term control of cellular reservoirs that maintain HIV-1 infection during treatment. 相似文献
997.
R?FoyEmail author MP?Eccles G?Jamtvedt J?Young JM?Grimshaw R?Baker 《BMC health services research》2005,5(1):50
Background
Improving the quality of health care requires a range of evidence-based activities. Audit and feedback is commonly used as a quality improvement tool in the UK National Health Service [NHS]. We set out to assess whether current guidance and systematic review evidence can sufficiently inform practical decisions about how to use audit and feedback to improve quality of care. 相似文献998.
999.
Acute corneal calcification following chemical injury 总被引:4,自引:0,他引:4
PURPOSE: To describe the clinical and ultrastructural features of 3 cases of acute corneal calcification following accidental chemical injury. METHODS: Three men presented over an 18-month period with unilateral eye injuries sustained when applying an industrial fire retardant. This product is predominantly a gypsum aggregate (calcium sulfate dihydrate) plaster combined under pressure with a set-time accelerator (aluminum sulfate). In each case the tear pH was initially alkaline, and the eyes were irrigated with phosphate-buffered saline according to protocol. Within hours a dense corneal opacity had developed that showed only minor resolution over 3 years of follow-up. Two eyes required corneal graft surgery for visual rehabilitation. Light and electron microscopy and energy dispersive analysis of x-rays (EDAX) was performed on excised tissue. RESULTS: Light and electron microscopy showed dense mineralization of the anterior stroma with discrete crystalline deposits in the deeper stroma. EDAX of the crystals showed high emission peaks for calcium and phosphorus. CONCLUSIONS: The insolubility, elemental composition, and ultrastructural appearance suggest that the opacity was caused by calcium phosphate deposition. The absence of phosphorus from the listed components of the fire retardant suggests that the use of phosphate-buffered irrigation fluid or the subsequent use of phosphate-buffered drops may have contributed to the deposition of this insoluble crystalline deposit. 相似文献
1000.
A diverse array of biologically active, lipid-soluble alkaloids have been discovered in amphibian skin. Such alkaloids include the following: the steroidal samandarines from salamanders, the batrachotoxins, histrionicotoxins, gephyrotoxins, and epibatidine from neotropical poison frogs (Dendrobatidae), the pumiliotoxins, allopumiliotoxins, homopumiliotoxins, and decahydroquinolines from certain genera of anurans from four families (Dendrobatidae, Mantellidae, Bufonidae, and Myobatrachidae), a variety of izidines (pyrrolizidines, indolizidines, quinolizidines, lehmizidines), pyrrolidines, piperidines, various tricyclics (related in structures to the coccinellines), and spiropyrrolizidines from the first three of these four families, the pseudophrynamines from one genus of Australian frogs, and a variety of unclassified alkaloids as yet of undetermined structure. With the exception of the samandarines and the pseudophrynamines, all alkaloids appear to be derived from dietary sources. Although only a few of the over 800 amphibian skin alkaloids have been detected in arthropods, putative arthropod sources for the batrachotoxins and coccinelline-like tricyclics (beetles), the pumiliotoxins (ants, mites), the decahydroquinolines, izidines, pyrrolidines, and piperidines (ants), and the spiropyrrolizidines (millipedes) have been discovered. Ants are likely sources for histrionicotoxins, lehmizidines, and tricyclic gephyrotoxins. Epibatidines represent an important alkaloid class without a putative dietary source. The structures for many of these alkaloids have been rigorously established, while the structures of others represent tentative proposals, based only on mass spectral and FTIR spectral data, along with analogies to structures of well-defined alkaloids. 相似文献